1. Field of Invention
The present embodiment of this invention generally relates to the games of pool and pocket billiards, and specifically to a training device for use in aiming a shot in pool and pocket billiards.
2. Prior Art
In the games of pool and pocket billiards, generally, a cue stick is used to strike and propel a cue ball toward an object ball so that when the object ball is struck by the cue ball, the object ball is directed into a pocket lining the game-playing surface. While it may seem easy in principle to aim a cue ball to collide with an object ball so that the latter is pocketed, in practice it is not always easy. It can require a bit of mental “gymnastics” for a player to achieve the correct aim-point for any shot other than one strait in as the games are played with spheres: a player must recognize that the cue ball can only contact the periphery of the object ball at exactly one radius of the cue ball from the center of the cue ball. Although many novice players can correctly determine where the object ball must be contacted by the cue ball to achieve a desired trajectory, these same players often aim the through the center of the cue ball at the object ball without accounting for the true contact point on the periphery of the cue ball. This method frequently results in a missed shot. Numerous hours of practice are needed for a player to correctly visualize the required contact points on the surfaces of both the cue ball and the object ball, and then use the correct aim-point during a shot to achieve the desired trajectories after a collision.
Inventors have developed aiming devices that attempt to show the correct cue ball aim-point, and to reduce the number of hours of practice required to achieve proficiency in the game. For example, an aiming device 15 in U.S. Pat. No. 4,337,943 to Stewart, 1982 Jul. 6, as depicted in FIG. 1, describes a marking device 16 that will leave a marking substance 17 on the felt of a pool table's playing surface 18 exactly one radius of a cue ball (not shown) away from an object ball 19 when one of the legs 20 of the device 15 is placed next to object ball 19 and device 15 is activated. Device 15 is then removed and a player (not shown) aims the cue ball at mark 17 deposited on playing surface 18 in order to contact object ball 19 at the required location.
Although Stewart's device 15 may show an aim point for a shot in pool or billiards as mark 17 deposited on surface 18, the aim point would be difficult to see from a distance due to its small size and two-dimensional nature. Since the target is a point that the cue ball is intended to roll over, it trains a player to aim with the base of the ball instead of its periphery as referenced by its center. Also, many pool table owners may object to a mark of any kind left by a device, however temporary, being placed on the table's felt.
Another aiming device 21 in U.S. Pat. No. 4,151,990 to Josenhans, 1979 May 1, as depicted in FIG. 2, describes a flat compliant structure with an arrow 22 at one end, an object ball locator 23 in the middle, and an aiming pattern 24 on the other end. Device 21 is placed flat upon playing surface 25 with arrow 22 pointing in the direction of travel desired for object ball 26. Object ball 26 is placed upon the midpoint of device 21 at the object ball locator 23 position. The player then shoots a cue ball 27 at aiming pattern 24 to make contact with object ball 26.
Josenhan's device 21 gives more aiming clues than Stewart's, but it is still only a two-dimensional target placed flat against playing surface 25 making it difficult to see for longer shots. As with all devices with aim-points that are not at the same height as the horizontal contact points of pool balls, a player must mentally make both a vertical and a horizontal aim-point adjustment to realize a desired contact on the periphery of the pool balls. While the flatness of Josenhans' device 21 would allow it to remain in place after a use during game play without interfering much with subsequent shots, its size would make it difficult to place near other balls. In addition, targeting object ball 26 requires the player to first pick up object ball 26 and place it on device 21 before device 21 can be used.
The aiming device in U.S. Pat. No. 5,401,215 to Pfost, 1993 Sep. 2, as depicted in FIG. 3, describes an object ball 28 with a surface coated with an array of colored dots 29, adjacent dots being dissimilarly colored. The player chooses a dot directly opposite the desired trajectory of object ball 28, and then shoots a cue ball (not shown) at the chosen dot (not shown) on object ball 28.
This device only shows where object ball 28 must be struck by a cue ball to achieve a desired trajectory; it does not show where a player must aim the cue ball to make contact with object ball 28 at a desired colored dot 29. A player is expected to intuitively aim for an imaginary spot that is separated from and perpendicular to the contact dot at a distance equal to the radius of the cue ball. Also, certain commonly used venues, like coin operated billiards tables, probably would not be used by a player for practice due to the necessity to pay for the return of object ball 28 each time it has been sunk. In order to practice actual game play, a full set of dotted object balls would be needed, increasing the expense to a player
Another aiming device 30, U.S. Pat. No. 3,947,026 to Scoutten, 1975 Apr. 24, as depicted in FIG. 4, describes a representative cue ball 30, cut in half with the flat side up, that is placed immediately adjacent an object ball 31, but opposite the desired trajectory of object ball 31. Device 30 is used as a visual indicator to show a player both the desired point of contact with object ball 31 and the point of aim for a cue ball (not shown.) Once a player has committed the point of aim to memory, aiming device 30 is removed and the player takes the shot.
Once device 30 is removed, however, there is no longer a target indicator at which the player is to aim. The player is required to recall what the sight picture was when the representative cue ball 30 was in place, and try to position an actual cue ball in the same spot next to object ball 31 when making a shot.
An aiming device 32 in U.S. Pat. No. 4,268,033 to Fontaine, 1981 May 19, as depicted in FIG. 5, describes a substantially u-shaped tunnel structure that is placed over object ball 33 so that object ball 33 abuts a specific reference point, object ball cradle 37, within the structure. Device 32 is aimed in the direction of the desired trajectory for object ball 33. A player must shoot cue ball 34 under a “cue ball spotter” 35 above the entrance to device 32 to make contact with object ball 33. Object ball 33 is then ejected through the other end of device 32.
One difficulty with Fontaine's device 32 is that after cue ball 34 makes contact with object ball 33, cue ball 34 can carom off object ball 33 into one of device 32's upright supports 36. A shot that is almost strait-on poses another problem-cue ball 34 may roll into device 32 and collide with object ball cradle 37, which hangs down from within the center of device 32. The form of device 32 is bulky and blocks the view, especially from the player's perspective, of playing surface 38 near object ball 33.
A similar concept to Fontaine's is presented in U.S. Pat. No. 6,827,651 to Davis, 2004 Dec. 7, as depicted in device 49 of FIG. 6, except the spotting and aiming mechanisms are handled by a light unit 43 and a few lasers. A projector body 39 houses these mechanisms above an object ball 40, and is supported by spider-like legs 41 extending to both sides of object ball 40. An alignment stop 42 positions object ball 40, and a light unit 43 projects a flat circle of light on playing surface 44 next to object ball 40 indicating where a player is to aim cue ball 45. A laser 46 in projector body 39 is used to aim device 49 along the desired trajectory for object ball 40; a second laser 47 projects a spot on the midpoint periphery of object ball 40 indicating the desired contact point with cue ball 45; side lasers 48 illuminate reference lines transverse to the longitudinal axis of device 49.
As with Fontaine's device, Davis's device's support legs 41 get in the way of cue ball 45 on certain shots after contact is made with object ball 40. The alignment stop 42 under projector body 39 which positions object ball 40 also gets in the way of cue ball 45 on shots where cue ball 45 would follow object ball 40 after contact. Light unit 47 producing the circle of light used as the aiming indicator for cue ball 45 is two dimensional as projected onto playing surface 44, and difficult to see at a distance. Davis's device 49 is battery operated and requires continual replacement of batteries as they run down. Device 49 would also be considerably more expensive to produce as compared to purely mechanical units due to the complexity of lasers and the light unit 47 in device 49. If a player is practicing with device 49 at a location with other pool tables and players in close proximity, the lasers from device 49 may project targeting lines on the other tables and players. Additionally, certain types of lasers may cause eye damage when inadvertently focused on the eye, limiting the proper use of device 49 to responsible adults.